I propose two features added to the current solution:
1) Admin can disable chat for the entire server
2) When either admin disables chat or a user hides chat-messages in his settings, the right-pane frame should be removed completely.
The second point is actually more important than the first in my opinion. I tried disabling the chat and now I still have the frame taking up space, but it's empty. As the screen shot below shows it's a bit annoying if you don't want the chat-functionality.

